CA2251371A1

CA2251371A1 - Oil, water and solvent resistant paper by treatment with fluorochemical copolymers

Info

Publication number: CA2251371A1
Application number: CA002251371A
Authority: CA
Inventors: John J. Fitzgerald
Original assignee: Individual
Current assignee: EIDP Inc
Priority date: 1996-04-12
Filing date: 1997-04-10
Publication date: 1997-10-23
Also published as: TW424121B; DE69702446T2; EP0892819B1; US5674961A; JP2000508693A; CN1127526C; AU2663697A; WO1997039036A1; DE69702446D1; CN1222166A; JP3723223B2; EP0892819A1; AU722085B2

Abstract

A copolymer composition for treating paper and paper products to impart water, oil or grease repellency comprising monomers copolymerized in the following percentages by weight: (a) from about 60 % to about 90 % of at least one monomer of formula (I): Rf-Q-A-C(O)-C(R)=CH2, wherein Rf is a C2-20 straight or branched-chain perfluoroalkyl group, R is H or CH3, A is O, S, or N(R'), wherein R' is H or a C1-14 alkyl, Q is C1-15 alkylene, C3-15 hydroxyalkylene, (CnH2n)(OCqH2q)m-, -SO2-NR'(CnH2n)-, or -CONR'(CnH2n)-, wherein R' is H or C14 alkyl, n is 1 to 15, q is 2 to 4, and m is 1 to 15; (b) from about 10 % to about 40 % of at least one monomer of formula (II): (R1)2N-CH2CH2-O-C(O)-C(R2)=CH2, wherein R1 is C1-3 alkyl, R2 is H or a C1-4 alkyl radical, and wherein the nitrogen is from about 40 % to 100 % salinized; and, (c) from about 1 % to about 7 % of at least one monomer of formula (III) or (IV): ClCH2-CH(OH)CH2-O-C(O)-C(R4)=CH2, or a mixture thereof, wherein R3 and R4 are each independently H or the same or different C1-4 alkyl radical is disclosed.

Description

CA 022~1371 1998-10-05 CH- 7~75 ~ A ' ' TITLE
OIL, WATER AND SOLVENT RESISTANT PAPER BY TREATMENT
WITH FL~JOROCHEMICAL COPOLYl\IERS

FIELD OF THE INVENTION
This invention relates to fluorochemical copolymers and their application to paper and similar products to impart repellency to water, oil, or grease.

BACKGROUND OF THE INVENTION
The paper industry makes a large variety of pack~ginP~ for food use. A
stain or leak-proof barrier is required for paper that comes into contact with oily, 0 greasy or watery foods. Polymeric barriers such as polyethylene are costly toapply to paper and interfere with its repulpability or recyclability after its intended use, and are being increasingly restricted by regulations. Fluorine-cont~ining chemicals and copolymers, collectively referred to as fluorochemicals, have beenused for a number of years to impart water, oil and grease resistance to substrates such as paper because of their effectiveness at low concentrations and their adaptability to conventional methods of m~nllf~cturing paper. For example, U.S.
Patent 4,147,851 of Raynolds issued April 3, 1979 discloses that copolymers comprising 50 to 85 weight % of a perfluoroaliphatic acrylatelmethacrylate monomer and 50 to 15 weight % dialkylaminoaLkyl acrylate/methacrylate monomer or the corresponding amine salt, qu~tPrn~ry or amine oxide monomer are useful in oil and water repellency applications. European Patent 234 601 teaches fluorochemical copolymers useful as paper-making additives which impart oil and water repellency and food stain resistance to ovenable paperboard.
The amino-cont~ining monomer is present at a level of 1% to 6% by weight.
Japan 50010820 teaches a polyurethane coating composition cont~ining a polar fluorine compound for providing good gloss and weather resistance to blend sponge.
Fluorochemicals are generally applied to such materials either by surface application to the paper or by addition to the paper pulp before the paper is formed. Surface application may be carried out by means such as spraying, dipping, roller-coating or padding to apply the fluorochemical to one or both sides of the essentially fini~hed product. This type of treatment has the advantage that the overall amount of fluorochemical on the paper is directly controllable sincethere is a limited opportunity for loss at this stage of the process. It has the AMENDED SHEET

CA 022~1371 1998-10-0~

disadvantage that the fluorochemical is applied primarily to the surface of the paper and may offer only limited protection to deeper liquid penetration.
Alternatively, the fluorochemical can be added to the paper pulp under appropriate conditions that all or the majority of the fluorochemical is retained by the paper after it is dewatered. In this type of treatment the fluorochemical isapplied throughout the thickness of the paper, not primarily just to the surface.

lA
AMENDED SHEET

CA 022~1371 1998-10-0~

wo 97/39036 PCT/USg7/05973 -This more uniform treatment is particularly important in providing resistance topenetrating liquids if the paper is creased or abraded in some areas. The disadvantage of this type of treatment is that special conditions must be established to insure that the fluorochemical is retained by the paper, i.e.. is not lost in the water removal step of paper formation. For either method of application, the key measurement of performance for these fluorochemicals is their ability to repel or resist materials such as oil, grease, water and similar materials at a low level of fluorine content.
Another important characteristic for these fluorochemicals is their stability o under high-shear conditions. In paper mills, these compounds are often transferred to the application area by high-shear pumps. In addition, they are typically applied to the paper from rollers, again operating under high-shear conditions. If the fluorochemical is unstable under these conditions, and deposits a coagulum on the rollers or the pumps, it can cause m~hine stoppage and generally poor 5 application performance.
Fluorine-cont~ining copolymers used for these applications frequently contain cationic groups in order to make them bond to cellulosic fibers, which are anionic under most conditions. These copolymers may be made by emulsion polymerization or solution polymerization. In emulsion polymerization, the 20 monomers are dispersed with a surfactant in an aqueous continuous phase and polymerization is initiated, forming an emulsion of surfactant-dispersed droplets.
This type of product has the potential problem that such emulsions are frequently unstable (i.e. coagulate) under the harsh, high-shear conditions encountered in commercial units. In solution polymerization, one or more of the monomers has a 2s solubilizing ability without the need for a surfactant. This type of product may form a solution or an emulsion, either of which may be more stable under harsh conditions than a surfactant-dispersed product. The use of such a fluorochemicalcopolymer requires a careful balance between the hydrophilic characteristics which make it soluble or dispersible in water and the hydrophobic characteristics 30 desirable in the fini~hPd paper products.
Therefore, in addition to their dispersion stability under high-shear conditions, another important criterion of performance for fluorochemical copolymers is the hydrophobic and oleophobic characteristics of the finished paper products. Still another criterion is achievement of these benefits with a 35 minimum of volatile materials released into the air during application to the paper or paper products. Thus there is a need for compositions which provide improved water. oil or grease repellency to paper and paper products, which are stable under .

CA 022~1371 1998-10-0~

wo 97/39036 PCT/US97/05973 high-shear conditions. and release a minimllm of volatile materials into the airduring application. The fluorochemical copolymers of the present invention meet these needs and show several key performance advantages over other fluorochemical copolymers previously used for such applications.

s SUMMARY OF THE INVENTION
The present invention comprises a copolymer composition which imparts water, oil or grease repellency to paper and paper products comprising monomers copolymerized in the following percentages by weight;
(a) from about 60 to about 90% of at least one monomer of formula I:

~ Rf-Q-A-C(O)-C(R)=CH2 wherein Rf is a straight or branched-chain perfluoroalkyl group of from 2 to about 20 carbon atoms, R is H or CH3, A is O, S, or N(R'), wherein R is H or an alkyl of from 1 to about 4 carbon atoms, Q is alkylene of l to about 15 carbon atoms, hydroxyalkylene of 3 to about 15 carbon atoms, (CnH2n)(OCqH2q)m-, -SO2-NR'(CnH2n)-, or-CONR'(CnH2n)-, wherein R' is H or an alkyl of 1 to about 4 carbon atoms, n is 1 to about 15, q is 2 to about 4,andmis I toabout 15;
(b) from about 10 to about 40% of at least one monomer of formula II:

(R1)2N-CH2cH2-O-c(o)-c(R2)=cH2 II
wherein 2s Rl is an alkyl group of from I to about 3 carbon atoms, R2 is H or an alkyl radical of I to about 4 carbon atoms, and wherein the nitrogen is from about 40% to 100% ~lini7~d; and, CA 022~1371 1998-10-0~

WO 97/39036 rCTlUS97/05973 (c) from about 1 to about 7% of at least one monomer of formula III or IV, or a mixture thereof:
/~ ' CH2 CH--CH2 O--C(O)--C(R3)=CH2 or Cl-CH2-CH(OH)CH2-O-C(O)-C(R4)=CH2; IV
wherein R3 and R4 are each independently H or the same or different alkyl radical of I to about 4 carbon atoms.
The present invention further comprises a method of treating paper or o paper products to impart water, oil, or grease repellency comprising application to the surface of the paper or paper product, or addition to the pulp prior to paper or paper product formation, of an effective arnount of the copolymer composition ofthe present invention as described above.
The present invention further comprises a paper or paper product which s has been treated with the copolymer composition of the present invention as described above, said tre~tment comprising application of the composition to thesurface of the paper or paper product, or addition of the composition to the pulp prior to formation of the paper or paper product. The treated paper or paper product has a fluorine content of from about 0.04% to about 0.10% by weight.

E~IFF DESCR~PTION OF T~F. FIGU~F.S
Figures lA, lB and lC depict three black filter cloths through which the copolymer solutions of comrnercial Sample A and of Examples 1, 2, respectively, were filtered. Figure I A (Sample A) shows white solid polymeric deposits, whileFigures lB and lC (Examples 1 and 2) filtered cleanly leaving no residue.

DF.TAlT,Fl) I~F.. SCI~TPTION OF THF. INVENTION
This invention comprises improved fluorochemical copolymers useful for imparting water, oil and grease resistance to paper and paper products. By paperproducts is meant paper, paperboard, cardboard and similar products which are made by dewatering a wood or cellulosic (including cotton) aqueous pulp. While 30 the following discussion applies to paper as an example it generally applies to other paper products as well.

CA 022~1371 1998-10-0~

Superior water, oil or grease repellency is imparted to paper and paper products by the addition of the fluorochemical copolymer compositions of the present invention. The composition is added to the paper or paper products in the form of a self-dispersed emulsion or dispersion in water or other solvent. The s composition is added either to the paper pulp before paper formation. or is applied to the essentially-finished paper. The copolymer composition of the present invention comprises monomers copolymerized in the following percentages bv weight~ relative to the total weight of the copolymers:
(a) from about 60 to about 90% of at least one monomer of formula I:
1 0 Rf-Q-A-C(O)-C(R)=CH2 wherein Rf is a straight or branched-chain perfluoroalkyl group of from 2 to about 20 carbon atoms, R is H or CH3, A is O, S, or N(R'), wherein R is H or an alkyl of from 1 to about 4 carbon atoms, Q is alkylene of 1 to about 15 carbon atoms, hydroxyalkylene of 3 to about 15 carbon atoms, -(CnH2n)(OCqH2q)m~~ ~SO2-NR~(cnH2n)-~ or -CONR'(CnH2n)-, wherein R' is H or an alkyl of 1 to about 4 carbon atoms, n is 1 to 15,qis2to4,andmis I to 15;
(b) from about 10 to about 40% of at least one monomer of forrnula II:

(Rl)2N-CH2cH2-O-c(o)-c(R2)=cH2 II
wherein R1 is an alkyl group of from 1 to about 3 carbon atoms, R2 is H or an alkyl radical of 1 to about 4 carbon atoms, and wherein the nitrogen is 40 to 100%
~s s~lini7P~l; and, (c) from about 1 to about 7% of at least one monomer of formula III or IV, or a mixture thereof:
/C~
CH2 CH--CH2--O--C(O)--C(R3) =CH2 III
or Cl-CH2-CH(OH)CH2-O-C(O)-C(R4)=CH2 IV;
wherein ... , , ~ . .. .

CA 022~1371 1998-10-0~

R3 and R4 are each independently H or the same or different alkyl radical of 1 to about 4 carbon atoms.
Preferably in the composition of the present invention in Formula I~ R4 is a straight chain perfluoroalkyl group of 2 to about 20 carbon atoms, A is O and Q
s is an alkylene of 1 to about 15 carbon atoms. More preferably the monomer of Formula I is a perfluoroalkylethyl acrylate having the formula CF3CF2(CF2)xC2H4OC(O)-C(H)=CH2 wherein x is an even integer from 4 to 18, or mixtures thereof. Most preferred is a perfluoroalkyl carbon chain length distribution (x) by weight of about 50% of 8-carbon, about 29% of 10-carbon, o about 11% of 12-carbon, and with smaller percentages of 6-carbon, 14-carbon and longer chain lengths. Preferably the monomer of Formula II is diethylaminoethyl methacrylate and the monomer of Formula III is glycidyl methacrylate.
The proportion of the monomer of Formula I is at least about 60% relative to the total weight of copolymer. If it is present in lower amounts, the repellency is unacceptably poor. The proportion should be less than about 90%. If it is present in higher amounts, the amounts of the monomer of Formula II and the monomer of Formula III or IV, or mixtures thereof, are too low, resulting in poor dispensability. Preferably the proportion of the monomer of Formula I in the copolymer is from about 79% to about 85% by weight for the best balance of dispersion stability, solubility and reactivity perfo~ ce.
Preferably the monomer of Formula II is diethylaminoethyl methacrylate which has undergone partial or full s~lini7~tion or quartt~rni7~tion. It must be at least about 40% s~lini7Pd for adequate solubili_ing effect, but may be as high as 100%. While a fully s~lini7P~l m~teri~l iS s~ti~f~ctory in performance, it releases an unnecessary amount of s~lini7in~ agent when the polymer is heated and cured.
Preferably the degree of s~lini7:~tion is between about 50% and 100%. The free amine portions of the resulting copolymer can then be reacted with a s~lini7ing agent such as acetic acid, resulting in the conversion of part or all of the amine moieties to the corresponding acetate. Alternatively, the s~lini7~tion reaction may be carried out on the amine group before the polymerization reaction with equally good results. The s~lini7.ing/ql~t~rni7ing group can be an acetate, halide, sulfate or other known s~lini7ing/ quaternizing group.
The proportion of the monomer of Formula II is at least about 10% for adequate solubilization. A proportion above about 40% will impair oil and water 3s repellency. Preferably the proportion of the monomer of Formula II in the copolymer is (as s~lini7P~) from about 13% to about 19% by weight.

CA 022~1371 1998-10-0~

~hile not wishing to be bound by theory, it is believed that the monomer of Formula III or IV may act as a reactive site for the polymer to covalently bond to the substrate surface. Preferably the monomer of Forrnula III is glycidvl methacrylate. It is present in a proportion of at least about 1% to have a noticeable effect. An amount above about 7% may not further improve performance.
Preferably the proportion of the monomer of Formula III or IV, or a mixture thereof, in the copolymer is from about 1% to about 5% by weight.
The polymerization of comonomers of Formula I, II, and III or IV or a mixture thereof, to prepare the composition of the present invention, is carried out o by contacting the monomers a solvent such as acetone, methylisobutyl ketone,ethyl acetate, isopro~ ol~ and other ketones, esters and alcohols or mixtures thereof. The polymerization is conveniently initiated by any free radical initiators, such as 2,2'-azobis(2,4-dimethylvaleronitrile. These are sold by the E.
I. du Pont de Nemours and Co., Wilmington, Delaware commercially under the name of "VAZO" 67, 52 and 64, and by Wako Chemicals USA, Ltd., under the name "V-501 ".
The following tests were used to evaluate the prOpGl lies of the treated paper with the inventive copolymers and com~d~ e examples: The Cobb Size Test as described in TAPPI 441 os-77 measures the absorptiveness of water in grams per square meter of paper surface using a water head pressure of one centimeter and a time of 120 seconds. The Turpentine Test for Grease Resi~t~n~e is also described in TAPPI T454 os-77, and measures the time in seconds elapsed before a red-stained turpentine penetrates the paper. A higher number indicates a greater grease resistance. The Ralston-Purina Grease Resi~t~n~e Test for Pet 2s Food Materials is described in the Ralston-Purina Company Pack~ging Reference Manual Volume 6. It measures the st~ining of paper using a specifically suppliedSynthetic Oil designed to duplicate the effect of ingredients in pet foods. A
higher number represents a greater degree of staining; i.e., poorer grease resistance. The Kit Test, described in TAPPI UM 557, measures the degree of ,o repellency and anti-wicking characteristics of paper treated with fluorochemical agents by dropping from a height of one inch a drop from one of a series of certain castor oil, toluene and heptane mixtures numbered from l to 12. The Kit Test Rating is the highest numbered solution not showing staining of the paper.
with a higher number indicating superior oil resistance.

.

CA 022~1371 1998-10-0~

WO 97/39036 PCTtUS97tO5973 EXAI~PT,F, 1 A vessel fitted with a stirrer, thermometer, and reflux condenser was charged with 673.5 parts of a fluoromonomer of formula I having the formula:
CF3CF2(CF2)xC~H4OC(O)-C(H)=CH2 wherein X = 6, 8, 10, 12, 14, 16, 18 in s the respective relative amounts of about 3%, 50%, 31%, 10%, 3%, 2% and 1%~
said monomer having an weight average molecular weight of 569; 119.5 parts of a monomer of formula II, N,N-diethylaminoethyl methacrylate; 19 parts of a monomer of formula III, glycidyl methacrylate; and 505 parts of methyl isobutyl ketone (MIBK). The charge was purged with nitrogen at 40~C for 30 minutes.
o "VAZO" 67 (0.6 parts) available from E. I. du Pont de Nemours and Co., Wilmington, DE was then added to initiate polymerization and the charge was stirred for 16 hours at 70~C under nitrogen.
A mixture of water (2435 parts) and acetic acid (59.5 parts) at room temperature was added to the above copolymer mixture at 70~C. The reflux condenser was replaced with a distillation colurnn and the MIBK was removed at reduced plCS~.Illc. A total of 3103 parts of copolymer solution was obtained. The copolymer solids (23.1%) cont~in~l 82.2% perfluoroalkylethyl meth~rrylate units, 15.4% N,N-diethylaminoethyl meth~rylate units and 2.4% glycidyl m.oth~rrylate units.
The polymer from above was applied to waterleaf paper (34 lb/3000 sq ft) (15 kg/288m2) by immersing the paper into one of several treating solutions, andthen passing the treated paper between squeeze rollers. Treating solutions were made by dispersing the above copolymer in 50 ppm hard water and hydroxyethylated starch. The concel.kdlions of copolymer in the treating solutions were adjusted to deposit 0.04%, 0.05%, 0.06%, 0.07%, 0.08% or 0.10%
fluorine, respectively, and 2.4% starch on the paper. The treated paper was cured in a heat press at 260~F (127~C) for 2 minutes and tested for oil, grease, solvent and water repellency. The oil, grease, solvent and water repellency results for Example 1 and a col,ll,dl~live commercial sample A are s~ ed in Table I
below. Based on information in the FDA Register, comrnercial sample A is an emulsion copolymer of a fluoro acrylate, 2-ethoxyethyl acrylate, diethylaminoethyl methacrylate methyl chloride salt, glycidyl methacrylate~ and octvl mercaptan using as emulsifier an ethoxylated amine salt and the polymerization process using a water soluble free radical initiator. It is available 3s as "SCOTCHI3AN" FC~45 from Minnesota Mining and Manufacturing Co. (3M) of Minneapolis, MN.

CA 022~1371 1998-10-0~

The Cobb Size results are an average of two trials. The Ralston-Purina Grease test is an average of four trials. The Turpentine Test is an average of two trials, with a "+" after a result indicating that a reading of at least 1800 seconds was obtained in at least one trial.

Table 1 Oil, Water, Solvent and Grease Repellency on 34 Lb Waterleaf Paper Fluorine Oi1 Ralston- Turpentine Cobb Sample Wt% KitPurina Resistance Size Ex. 1 0.04% 7 9 420 37 0.05% 8 0 1~00 + 23 0.06% 8 0 1800 + 23 0.07% 10 0 1800 + 25 A 0.04% 6 100 30 37 0.06% 7 0 580 28 0.08% 9 0 1380 + 27 0.10% 10 0 1420 + 23 The copolymer from Example 1 clearly shows better oil and solvent lo repellencies at comparable fluorine levels in the Turpentine Test for Grease Resistance and the Ralston-Purina Grease Resistance test at lower applied fluorine levels. The Cobb Size test results show little difference for the two fluoropolymers.

This example demonstrates the coI~lp~dlive performance of a copolymer ple~ ed according to the tea~hing~ of US 4,147,851: i.e., a copolymer prepared without the above third component (c), a monomer of Formula III or IV, or a mixture thereof.
A vessel fitted with a stirrer, thermometer and reflux condenser was 20 charged with 70 parts of a fluoromonomer of formula I having the formula:

CF3CF2(CF2)XC2H4C-O-C(O)-C(CH3)=CH2 wherein X = 4, 6, 8, 10, 12, 14, 16, 18, 20 in the respective relative amounts of about 5%, 35%, 30%, 14%, 6%, 4%, 3%, 2% and 1%, said monomer having an weight average molecular weight of 543; 30 parts of a monomer of formula II, AMENDED SHEET

-N.N-diethylaminoethyl methacrylate; and 100 parts of isopropanol. The charge was purged with nitrogen for 30 minutes at 30~C. "VAZO" 67 (0.5 parts) available from E. I. du Pont de Nemours and Co., Wilmington, DE was then added to initiate polymerization and the charge was stirred for 18 hours at 65~Cunder nitrogen.
Peracetic acid (24.3 parts of a 42% solution in acetic acid) was dripped into the copolymer solution at 65~C. On completion of the addition the reaction mass was stirred for an additional hour at 65~C. Water (200 parts) was added to the above copolymer mixture yielding a total of 414 parts of copolymer solution 0 with solids (24%) cont~inin~ about 70% perfluoroalkylethyl methacrylate units and about 30% N,N-diethylaminoethyl methacrylate amine oxide units. The above polymer solution is used as is, or is distilled at atmospheric or reduced pressure.
The polymer from Example 2 was applied to unbleached Kra~t paper (56 Ib/3000 sq ft) (25 kg/288m2) by inunersing the paper into the treating solution,5 passing the treated paper between squeeze rollers and curing in a heat press at 260~F (127~C) for 2 minlltes The treating solutions were made by dispersing the above copolymer in 50 ppm hard water and no starch. The wet pick-up of the paper was adjusted to deposit 0.06%, 0.08%, and 0.10% fluorine. The oil and water repellency results are summarized in Table 2. Included in Table 2 are data20 obtained by similarly applying Example 1 and commercial sample A.
Table 2 Oi~ Water. Sol~ent and GrP~~ Repellency o-~ Unhl~a~hed Kraft Paper FluorioeOil n~lctc- Tu~ Cobb Sample Wt% KitPurina Resistance Size Ex. 1 0.04% 5 22 30 52 0.06% 7 0 1020 + 26 0.08% 8 0 1740 + 25 0.10% 9 0 1800 + 26 Ex. 2 0.04% 5 0 45 25 0.06% 6 0 150 24 0.08% 7 0 180 24 0.10% 7 0 1470 + 23 A 0.04% 5 47 90 25 0.06% 6 0 300 24 0.08% 7 o 1800 + 24 o.lo% 9 o 1800 + 24 CA 022~1371 1998-10-0~

The above table demonstrates that the inventive copolymer from Example l is significantly superior to that prepared in Example 2 in the Oil Kitand Turpentine Resistance Tests, although inferior at the 0.04% fluorine level in the Ralston-Purina Grease Resistance Test. The Example 1 copolymer exhibits 5 generally similar overall performance to the sample A on this particular paper.
The most striking difference in performance of the above copolymers is their dispersion stability under high shear conditions. This was tested in the following manner. A solution of each copolymer in water was prepared by adding a dispersion cont~ining 10 parts of polymer solids to 90 parts of distilled water.
o This was circulated through a Viking gear pump at an approximate rate of 1200 milliliters/minute and a t~ el~Lule of 30~C for 3.5 hours.
The recirculated copolymer solution was next filtered through a black filter cloth and e~rninçd for insoluble residue. Copies of the resnlting filter cloths are shown in Figure 1. The copolymers from Examples 1 and 2 filtered 5 cleanly through the filter cloth leaving no residue. The recirculated comrnercial sample A showed excessive white polymeric deposits, indicating poor dispersion stability under these high shear conditions.

F.XAl~IPl.F.~ 3 to 9 Examples 3 to 9 were ple~ ed according to the general procedures 20 exemplified by either Example 1 or Example 2, with appl.)~ e changes as required depending on whether an acrylate, methacrylate or other fluoromonomer of Formula I was used, whether a third component (c~(a monomer of Formula III
or IV or mixture thereof) was added or not, and whether the resulting copolymer was reacted with acetic acid or peracetic acid. The compositions of copolymer 25 examples 3 to 9 as so prel)a~ed are summarized in Table 3 below in weight %:
For ease of reference, the composition of the copolymer ~e~ d in example 1 is also included.

wo 97/39036 PCT/US97/05973 Table 3 Compositions of Col~olymer Exa~ples 3 to 9 ~ nc ;~r .Uono ~ of ~l~nc --ofof Formula Quat~. g Formula I Formula 11 III or IV A~Tent FY~ rl~ AcrylMethFX-14 DEAM GMA Acetic Peracetic 82 - - I 5.42.4 6.8 3 82 - - I S.42.4 - 3 .2 4 - 82 - I 5.42.4 6.0 - - 20 - - 8.2 6 80 - - 20 - I 1.3 7 - 70 - 30 - 5.7 --8 - - 70 30 - - 12.3 9 - - 74 26 - 7.7 Notes: The peracetic acid used was a 32% by weight solution in acetic s acid. The monomer of Formula I used in Examples 8 and 9 was a commercially available fluoromonomer FX-14 available from the 3M Company, Minneapolis, MN. Acryl. stands for acrylate. Meth. stands for methacrylate. DEAM stands for diethylaminoethyl methacrylate. GMA stands for glycidyl methacrylate.
The copolymers from Examples 3 to 9 were applied to unbleached Kraft lo paper (56 lb/3000 sq ft) by immersing the paper into the treating solution, passing the treated paper between squeeze rollers and curing in a heat press at 260~F
(127~C) for 2 minl-tes The treating solutions were made by dispersing the above copolymer in 50 ppm hard water. The wet pick-up of the paper was adjusted to deposit 0.06%, 0.08%, and 0.10% fluorine. Repellency results are summarized in 1 5 Table 4. ND indicates not cletennin~l Comparable tests from Table 2 for the copolymer of Example 1 are included for easy reference.
Table 4 Repellency Tests on F~ 3 to 9 on Ur~hlearhed Kraft Paper Fluorine Oil Ralston Tur~,. -Sample Wt% Kit -Purin~ ~2 ~ ~ - c e Ex. l 0.04% ~ 22 30 0.06% 7 0 1 020+
0.08% 8 0 l 740+
0.10% 9 0 1800+

WO 97/39036 rCT/US97105973 -Fluorine Oil Ralston Turt,~Llille Sample Wt% Kit -Purina Resistance Ex. 3 0.04% 2 0 60-0.06% 4 0 1050 0.08% 5 0 810 0. 1 0% 6 0 1 800+
Ex. 4 0.06% 0 52 30 0.10% 4 0 60 Ex. 5 0.06% 6 0 150 0. 1 0% 7 0 1 800 Ex. 6 0.05% 1 5 105 0.08% 5 0 30 Ex. 7 0.04% 5 14 90 0.06% 6 1 1 50 0.08% 6 1 1 105 0.10% 6 12 300 Ex. 8 0.06% 4 0 30 0.10% 6 0 105 E~. 9 0.05% 5 24 ND
0.08% 6 0 ND

The copolymer of Example 3 is similar to that of Example 1 except that it is reacted with peracetic acid instead of acetic acid. While Example 3 shows improvement over Example 1 in the Ralston-Purina Test, it is inferior in the Kit5 and Turpentine ~esi~t~nce Tests.
The copolymer of Example 4 is similar to that of Example I except for use of a methacrylate with a broader distribution of perfluoroalkyl chain length than the acrylate. Example 4 is much inferior to Example I in oil, turpentine and grease repellency.
o The copolymers of Example 5 and 6 which lack the small amount of monomer of Formula III or IV found in Example 1 are inferior in ~ c~lline and oil resistance.
The copolymer of Example 7 is prepared according to the te~cllin~ of US
4~147.851 and is clearly deficient in the oil, Ralston-Purina and turpentine tests.
s The copolymers of Examples 8 and 9 are also deficient in these tests compared to Example 1.

Claims

WHAT IS CLAIMED IS:

1. A copolymer composition for treating paper and paper products to impart water, oil or grease repellency comprising monomers copolymerized in the following percentages by weight:
(a) from 60% to 90% of at least one monomer of formula I:

R f-Q-A-C(O)-C(R)=CH2 I
wherein R f is a straight or branched-chain perfluoroalkyl group containing from 2 to 20 carbon atoms, R is H or CH3, A is O, S, or N(R'), wherein R' is H or an alkyl of from 1 to 4 carbon atoms, Q is alkylene of 1 to about 15 carbon atoms, hydroxyalkylene of 3 to 15 carbon atoms, (C n H2n)(OC qH2q)m-, -SO2-NR'(C n H2n)-, or -CONR'(C n H2n)-, wherein R' is H or alkyl of from 1 to 4 carbon atoms, n is 1 to 15, q is 2 to 4, and m is 1 to 15;
(b) from 10% to 40% of at least one monomer of formula II:
(R1)2N-CH2CH2-O-C(O)-C(R2)=CH2 II
wherein R1 is an alkyl group containing from 1 to 3 carbon atoms, R2 is H or an alkyl radical of 1 to 4 carbon atoms, and wherein the nitrogen is from 40% to 100% salinized and, (c) from 1% to 7% of at least one monomer of formula III or IV, or a mixture thereof:

or C1-CH2-CH(OH)CH2-O-C(O)-C(R4)=CH2 IV, wherein R3 and R4 are each independently H or the same or different alkyl radical of 1 to 4 carbon atoms.

2. The composition of Claim 1 wherein for the monomer of formula I, R f is a straight chain perfluoroalkyl group of 2 to 20 carbon atoms, A is O, and Q is alkylene of 1 to 15 carbon atoms.

3. The composition of claim 1 wherein formula I is perfluoroalkylethyl acrylate, formula II is diethylaminoethyl methacrylate, and Formula III is glycidyl methacrylate.

4. The composition of Claim 3 wherein the monomer of Formula I is CF3CF2(CF2)xC2H4OC(O)-C(H)=CH2 wherein x is an even integer from 4 to 18 or mixtures thereof.

5. A method of treating paper or paper products to impart water, oil or grease repellency comprising application to the surface of the paper or paper product, or addition to the pulp prior to paper or paper product formation, of an effective amount of a composition comprising monomers copolymerized in the following percentages by weight:
(a) from 60% to 90% of at least one monomer of formula I:
R f-Q-A-C(O)-C(R)=CH2 wherein R f is a straight or branched-chain perfluoroalkyl group containing from 2 to 20 carbon atoms, R is H or CH3, A is O, S, or N(R'), wherein R' is H or an alkyl of from 1 to about 4 carbon atoms, Q is alkylene of 1 to 15 carbon atoms, hydroxyalkylene of 3 to 15 carbon atoms, -(C n H2n)(OC q H2q)m-, -SO2-NR'(C n H2n)-, or -CONR'(C n H2n)-, wherein R' is H or alkyl of from 1 to 4 carbon atoms, n is 1 to 15, q is 2 to 4, and m is 1 to 15;
(b) from 10% to 40% of at least one monomer of formula II:

(R1)2N-CH2CH2-O-C(O)-C(R2)=CH2 II

wherein R1 is an alkyl group containing from 1 to 3 carbon atoms, R2 is H or an alkyl radical of 1 to 4 carbon atoms, and wherein the nitrogen is from 40% to 100% salinized; and, (c) from 1% to about 7% of at least one monomer of formula III or IV, or a mixture thereof:

or Cl-CH2-CH(OH)CH2-O-C(O)-C(R4)=CH2 IV, wherein R3 and R4 are each independently H or the same or different alkyl radical of 1 to 4 carbon atoms.

6. The method of Claim 5 wherein the effective amount is such to deposit from 0.04 to 0.10 weight percent fluorine.

7. The method of claim 6 wherein formula I is perfluoroalkylethyl acrylate, formula II is diethylaminoethyl methacrylate, and formula III is glycidyl methacrylate.

8. A paper or paper product which has been treated with a composition comprising monomers copolymerized in the following percentages by weight:
(a) from about 60% to 90% of at least one monomer of formula I:

R f-Q-A-C(O)-C(R)=CH2 I
wherein R f is a straight or branched-chain perfluoroalkyl group containing from 2 to 20 carbon atoms, R is H or CH3, A is O, S, or N(R'), wherein R' is H or an alkyl of from 1 to 4 carbon atoms, Q is alkylene of 1 to about 15 carbon atoms, hydroxyalkylene of 3 to 15 carbon atoms, -(C n H2n)(OC q H2q)m-, -SO2-NR'(C n H2n)-, or -CONR'(C n H2n)-, wherein R' is H or an alkyl of from 1 to 4 carbon atoms, n is 1 to 15, q is 2 to 4, and m is 1 to 15;

(b) from 10% to 40% of at least one monomer monomers of formula II:

(R1)2N-CH2CH2-O-C(O)-C(R2)=CH2 II
wherein R1 is an alkyl group containing from 1 to 3 carbons, R2 is H or an alkyl radical of 1 to 4 carbon atoms, and wherein the nitrogen is from about 40% to 100% salinized; and, (c) from 1% to 7% of at least one monomer of formula III or IV, or a mixture thereof:

or Cl-CH2-CH(OH)CH2-O-C(O)-C(R4)=CH2 IV, wherein R3 and R4 are each independently H or the same or different alkyl radical of 1 to about 4 carbon atoms, wherein said paper or paper product after treatment has a fluorine content of from 0.04% to 0.10% by weight.